Isolator that can handle high current draw (1 Viewer)

[Dirty Koala]

I have a 5.9 liter Cummins 6BT in my 80 series which requires two 1000CCA start batteries wired in paralell. The Cummins starter will draw about 450 amps on start up, which means I need to rethink my backup battery setup...the Hellroaring BIC cant handle that much amperage.

I have two start batteries under the hood and a 3rd deep cycle group 31 built into my storage drawers which powers up my fridge and other accessories...I may add a 2nd deep cycle to the AUX bank.

I am going to be using a Redarc BCDC1225D DC to DC charger to keep that AUX deep cycle bank charged, I will also be hooking a solar panel into the BCDC once I figure out a good mounting solution.

I would like the security of being able to link the starting bank and AUX bank to jump start myself if needed.

Question: What options do I have for an isolator/combiner that will handle the current without getring damaged.

 

[Douglas S]

Blue Sea ACR. I have one, works flawlessly and handles 500A continuous. You could also just use a high current relay with manual control if you don't need the voltage sensing disconnect/reconnect.

ML-ACR Automatic Charging Relay with Manual Control - 12V DC 500A - Blue Sea Systems

 

[Dirty Koala]

Thanks Doug...I stumbled across the same unit late last night, looks like it will be a perfect combination to go with a Redarc BCDC1225D.

I think with this Bluesea ACR and manual control I will be able to leave the start and AUX banks separated under normal driving conditions. I would want the BCDC to control the charging of the Aux bank rather than the Bluesea.

When I setup camp and put out the solar panels, I could set the blue sea to Auto, which will allow the starting bank to get charged by solar once the Aux bank reaches about 13v. I like this since it gives me security of being able to top up the start batteries.

If I need to jump start myself, manually switch the ACR to join both banks and then fire up the motor.

 

[Dirty Koala]

Blue Sea ACR. I have one, works flawlessly and handles 500A continuous. You could also just use a high current relay with manual control if you don't need the voltage sensing disconnect/reconnect.

ML-ACR Automatic Charging Relay with Manual Control - 12V DC 500A - Blue Sea Systems

Do you have any pics of where you mounted your switch? Will it fit in an 80 series rectangle switch hole

 

[Douglas S]

Do you have any pics of where you mounted your switch? Will it fit in an 80 series rectangle switch hole

This is the best pic I have. The Contura style switches fit, but you will have to file the hole in the dash slightly larger.

Also the blue sea switch label is designed for vertical mounting. I changed it on my other switches, but haven't bothered doing anything with the ACR switch as the only thing that really matters is if the light is on or off, I rarely manually disconnect or combine the batteries and it's easy to determine which position you move the switch to based on whether the status light is on or off.

You'll have different mounting options with the later dash, but the holes are the same size.

 

[rusty_tlc]

I had dual batteries in a GMC. The main was isolated from the aux except for a standard trailer relay on the charge wire.
I am not entirely sure why people feel the need to use a power relay to self rescue. If you carry jumper cables just use them, this is how I did it for years. You do carry jumper cables don't you? Why add complexity to a system?
Since your Aux is built into the storage system I would suggest building a set of jumpers long enough to reach the aux. This way you can help yourself and others.

 

[Dirty Koala]

Perfect, I didn't realize these were contura. I have 3 ARB airlocker switches on the left of the steering wheel that I need to remove since I replace my airlockers with Harrops...those holes are filed larger already!

 

[Dirty Koala]

I had dual batteries in a GMC. The main was isolated from the aux except for a standard trailer relay on the charge wire.
I am not entirely sure why people feel the need to use a power relay to self rescue. If you carry jumper cables just use them, this is how I did it for years. You do carry jumper cables don't you? Why add complexity to a system?
Since your Aux is built into the storage system I would suggest building a set of jumpers long enough to reach the aux. This way you can help yourself and others.

When it is 5 degrees outside, the most likely time I am going to need that extra juice, the last thing I want to do is go digging for my jumper cables, roll the rear seat forward, find a screwdriver, unscrew the battery box lid, hook up the jumper leads, jump start myself and then have to pack everything away. I would rather, push a button and start the truck. I would rather keep the jumper leads in the drawers for when others need help. I have had this setup, albeit a hellroaring BIC isolator for years and the self start feature is very nice...I don't plan on going back to purely cables.